The CORE of the Program Project is designed to carry out two key functions, which are: (a) support of major shared equipment and shared facilities, as well as provision of general infrastructure for the Program, and (b) development of promising new technologies that are important to further advances in one or more of the Projects. Examples of major equipment supported by the CORE are three electron microscopes, computers, a high precision microdensitometer, a 10-liter bioreactor, and a variety of smaller items of equipment that are used routinely in specimen preparation and electron microscopy. Staff support is provided for computer-systems management, maintenance of equipment, in-house modification and instrumentation,and general housekeeping. Three areas of technology development are proposed. The first of these will provide direct electronic readout of spot-scan images and of electron diffraction patterns by means of an improved CCD camera, optimized for the 400 keV electron microscope. The second will pursue preliminary, low-budget studies to determine the feasibility of expressing membrane proteins in immortalized type 2 lung cells, in such a fashion that the protein is targeted to the lipid-bilayer surfactant material. The third will carry out preliminary studies to determine whether well-diffracting, 2-D protein crystals can be prepared by adsorption to a lipid monolayer, and can be transferred to EM grids for high resolution structural studies. All of the functions of the CORE are intended to facilitate the successful execution of the specific aims of the associated projects within the Program project, by providing resources needed in common and by advancing the technical capabilities of these resources. The high resolution structural data that is obtained as a result is of fundamental importance in a variety of areas of Cell and Molecular Biology.